1 | /* |
2 | * \file drm_scatter.c |
3 | * IOCTLs to manage scatter/gather memory |
4 | * |
5 | * \author Gareth Hughes <gareth@valinux.com> |
6 | */ |
7 | |
8 | /* |
9 | * Created: Mon Dec 18 23:20:54 2000 by gareth@valinux.com |
10 | * |
11 | * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. |
12 | * All Rights Reserved. |
13 | * |
14 | * Permission is hereby granted, free of charge, to any person obtaining a |
15 | * copy of this software and associated documentation files (the "Software"), |
16 | * to deal in the Software without restriction, including without limitation |
17 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
18 | * and/or sell copies of the Software, and to permit persons to whom the |
19 | * Software is furnished to do so, subject to the following conditions: |
20 | * |
21 | * The above copyright notice and this permission notice (including the next |
22 | * paragraph) shall be included in all copies or substantial portions of the |
23 | * Software. |
24 | * |
25 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
26 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
27 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
28 | * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR |
29 | * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, |
30 | * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER |
31 | * DEALINGS IN THE SOFTWARE. |
32 | */ |
33 | |
34 | #include <linux/mm.h> |
35 | #include <linux/slab.h> |
36 | #include <linux/vmalloc.h> |
37 | |
38 | #include <drm/drm.h> |
39 | #include <drm/drm_drv.h> |
40 | #include <drm/drm_print.h> |
41 | |
42 | #include "drm_legacy.h" |
43 | |
44 | #define DEBUG_SCATTER 0 |
45 | |
46 | static void drm_sg_cleanup(struct drm_sg_mem * entry) |
47 | { |
48 | struct page *page; |
49 | int i; |
50 | |
51 | for (i = 0; i < entry->pages; i++) { |
52 | page = entry->pagelist[i]; |
53 | if (page) |
54 | ClearPageReserved(page); |
55 | } |
56 | |
57 | vfree(addr: entry->virtual); |
58 | |
59 | kfree(objp: entry->busaddr); |
60 | kfree(objp: entry->pagelist); |
61 | kfree(objp: entry); |
62 | } |
63 | |
64 | void drm_legacy_sg_cleanup(struct drm_device *dev) |
65 | { |
66 | if (drm_core_check_feature(dev, feature: DRIVER_SG) && dev->sg && |
67 | drm_core_check_feature(dev, feature: DRIVER_LEGACY)) { |
68 | drm_sg_cleanup(entry: dev->sg); |
69 | dev->sg = NULL; |
70 | } |
71 | } |
72 | #ifdef _LP64 |
73 | # define ScatterHandle(x) (unsigned int)((x >> 32) + (x & ((1L << 32) - 1))) |
74 | #else |
75 | # define ScatterHandle(x) (unsigned int)(x) |
76 | #endif |
77 | |
78 | int drm_legacy_sg_alloc(struct drm_device *dev, void *data, |
79 | struct drm_file *file_priv) |
80 | { |
81 | struct drm_scatter_gather *request = data; |
82 | struct drm_sg_mem *entry; |
83 | unsigned long pages, i, j; |
84 | |
85 | DRM_DEBUG("\n" ); |
86 | |
87 | if (!drm_core_check_feature(dev, feature: DRIVER_LEGACY)) |
88 | return -EOPNOTSUPP; |
89 | |
90 | if (!drm_core_check_feature(dev, feature: DRIVER_SG)) |
91 | return -EOPNOTSUPP; |
92 | |
93 | if (request->size > SIZE_MAX - PAGE_SIZE) |
94 | return -EINVAL; |
95 | |
96 | if (dev->sg) |
97 | return -EINVAL; |
98 | |
99 | entry = kzalloc(size: sizeof(*entry), GFP_KERNEL); |
100 | if (!entry) |
101 | return -ENOMEM; |
102 | |
103 | pages = (request->size + PAGE_SIZE - 1) / PAGE_SIZE; |
104 | DRM_DEBUG("size=%ld pages=%ld\n" , request->size, pages); |
105 | |
106 | entry->pages = pages; |
107 | entry->pagelist = kcalloc(n: pages, size: sizeof(*entry->pagelist), GFP_KERNEL); |
108 | if (!entry->pagelist) { |
109 | kfree(objp: entry); |
110 | return -ENOMEM; |
111 | } |
112 | |
113 | entry->busaddr = kcalloc(n: pages, size: sizeof(*entry->busaddr), GFP_KERNEL); |
114 | if (!entry->busaddr) { |
115 | kfree(objp: entry->pagelist); |
116 | kfree(objp: entry); |
117 | return -ENOMEM; |
118 | } |
119 | |
120 | entry->virtual = vmalloc_32(size: pages << PAGE_SHIFT); |
121 | if (!entry->virtual) { |
122 | kfree(objp: entry->busaddr); |
123 | kfree(objp: entry->pagelist); |
124 | kfree(objp: entry); |
125 | return -ENOMEM; |
126 | } |
127 | |
128 | /* This also forces the mapping of COW pages, so our page list |
129 | * will be valid. Please don't remove it... |
130 | */ |
131 | memset(entry->virtual, 0, pages << PAGE_SHIFT); |
132 | |
133 | entry->handle = ScatterHandle((unsigned long)entry->virtual); |
134 | |
135 | DRM_DEBUG("handle = %08lx\n" , entry->handle); |
136 | DRM_DEBUG("virtual = %p\n" , entry->virtual); |
137 | |
138 | for (i = (unsigned long)entry->virtual, j = 0; j < pages; |
139 | i += PAGE_SIZE, j++) { |
140 | entry->pagelist[j] = vmalloc_to_page(addr: (void *)i); |
141 | if (!entry->pagelist[j]) |
142 | goto failed; |
143 | SetPageReserved(entry->pagelist[j]); |
144 | } |
145 | |
146 | request->handle = entry->handle; |
147 | |
148 | dev->sg = entry; |
149 | |
150 | #if DEBUG_SCATTER |
151 | /* Verify that each page points to its virtual address, and vice |
152 | * versa. |
153 | */ |
154 | { |
155 | int error = 0; |
156 | |
157 | for (i = 0; i < pages; i++) { |
158 | unsigned long *tmp; |
159 | |
160 | tmp = page_address(entry->pagelist[i]); |
161 | for (j = 0; |
162 | j < PAGE_SIZE / sizeof(unsigned long); |
163 | j++, tmp++) { |
164 | *tmp = 0xcafebabe; |
165 | } |
166 | tmp = (unsigned long *)((u8 *) entry->virtual + |
167 | (PAGE_SIZE * i)); |
168 | for (j = 0; |
169 | j < PAGE_SIZE / sizeof(unsigned long); |
170 | j++, tmp++) { |
171 | if (*tmp != 0xcafebabe && error == 0) { |
172 | error = 1; |
173 | DRM_ERROR("Scatter allocation error, " |
174 | "pagelist does not match " |
175 | "virtual mapping\n" ); |
176 | } |
177 | } |
178 | tmp = page_address(entry->pagelist[i]); |
179 | for (j = 0; |
180 | j < PAGE_SIZE / sizeof(unsigned long); |
181 | j++, tmp++) { |
182 | *tmp = 0; |
183 | } |
184 | } |
185 | if (error == 0) |
186 | DRM_ERROR("Scatter allocation matches pagelist\n" ); |
187 | } |
188 | #endif |
189 | |
190 | return 0; |
191 | |
192 | failed: |
193 | drm_sg_cleanup(entry); |
194 | return -ENOMEM; |
195 | } |
196 | |
197 | int drm_legacy_sg_free(struct drm_device *dev, void *data, |
198 | struct drm_file *file_priv) |
199 | { |
200 | struct drm_scatter_gather *request = data; |
201 | struct drm_sg_mem *entry; |
202 | |
203 | if (!drm_core_check_feature(dev, feature: DRIVER_LEGACY)) |
204 | return -EOPNOTSUPP; |
205 | |
206 | if (!drm_core_check_feature(dev, feature: DRIVER_SG)) |
207 | return -EOPNOTSUPP; |
208 | |
209 | entry = dev->sg; |
210 | dev->sg = NULL; |
211 | |
212 | if (!entry || entry->handle != request->handle) |
213 | return -EINVAL; |
214 | |
215 | DRM_DEBUG("virtual = %p\n" , entry->virtual); |
216 | |
217 | drm_sg_cleanup(entry); |
218 | |
219 | return 0; |
220 | } |
221 | |